Linerless closure



June 14, 1966 I. H- MILLER ETAL 3,255,909

LINERLESS CLOSURE Filed Jan. 13, 1964 INVENTORS IRA H. MILLER ATTORNEYSUnited States Patent 3,255,909 LTNERLESS OLGSURE Ira H. Miller,Lambertville, Mich, and Ned J. Smalley,

Toledo, Cthio, assignors to Uweusdliinois End, a corporation of OhioFiled Jan. 13, 1964, Ser. No. 337,443 2 Claims. ((11. 21543) This caserelates generally to a linerless closure and, more particularly, to thecombination of a container and a linerless closure.

The closure industry has long sought a closure which would efifectivelyseal a container from leakage of liquid contents without the necessityof providing such closure with a gasket. There are numerous linerlessclosures on the market as well as patents relating to molded plasticlinerless closures; however, none have been completely effective inproducing a leak-proof seal between the container to which it is afiixedand the sealing element of the closure. To be completely effective, itis necessary that the seal between the closure and its associatedcontainer be liquid-tight not only upon the initial application of theclosure to the container but also upon resealing.

Many of the linerless closures on the market or described in patentsrely upon a downwardly and inwardly directed sealing fin which dependsfrom the closure top panel to effect a sealing engagement with thecontainer. Such inwardly directed sealing fin engages the rim of itsassociated container and, as the closure is tightened thereon, is forcedupwardly toward the closure top panel. The upward movement of thesealing fin causes the lower marginal edge thereof to be urged inwardlytoward the longitudinal axis of the closure skirt, thereby reducing thediameter of the circle defined by such sealing fin lower marginal edge.As a result, the lower portion of the sealing fin becomes wrinkled orcorrugated thereby preventing the attainment of an effective seal.

Other types of linerless closures have various styles and configurationsof sealing fins, some of which rest directly on the top of the rim ofthe container mouth to which the closure is afiixed and others which fitwithin the mouth of the container. While many of these linerlessclosures are satisfactory in some respects, to my knowledge none havemet with widespread acceptance because they are either too complicatedand too expensive or they simply do not provide an effective seal.

As pointed out above, one of the essential requirements of a linerlessclosure is that it be effective upon rescaling. Thus, it is highlydesirable to use linerless closures in the packaging of toiletries andsimilar items of such a nature that only a portion of the contents aredispensed from the container at each use, the container then beingreclosed to await the next use. Frequently such reclosed container iscarried on overnight trips and, accordingly, is carried in luggage whereit will rarely be in an upright position. It is obvious that the failureof such closure to attain a liquid-tight seal with its associatedcontainer upon reapplication thereto makes the closure virtuallyworthless.

Accordingly, it is an important object of this invention to provide aclosure-container combination which will be highly effective inproviding a liquid-tight seal both upon the initial application of theclosure to the container and upon rescaling.

Despite the work done in developing various styles of linerlessclosures, it is apparent that virtually no attention has been given todeveloping a container neck finish and a linerless closure for use incombination. It is a specific object of the present invention to providea novel combination of a container neck finish and a linerless closure.

More particularly, it is an object of the present invention to providethe above combination characterized in Patented June 14, 1966 that thesealing contact between the closure and the container extends over asubstantial area.

It is afurther object of the present invention to provide a linerlessclosure which provides an effective seal on the container neck finishfor all types of liquids and which is relatively simple and economicalto manufacture.

Additional objects and advantages of the present invention will becomereadily apparent from the following detailed description taken inconjunction with the annexed sheet of drawings on which:

.FIGURE 1 is a sectional elevational view of the closure portion of thepresent invention;

FIGURE 2 is a sectional elevational view showing the closure partiallyengaged to the container neck;

FIGURE 3 is a view similar to FIGURE 2 showing the closure-containercombination with the closure being in full sealing position with thecontainer neck.

Referring now to the drawings, there is shown a closure generallydesignated 10 having a top panel portion 12 and a depending annularskirt 14. The closure as shown is provided with inwardly facing threads16 formed on the skirt 14 for securing the closure to a container neck.Depending downwardly and outwardly from the top panel 12 is an annularsealing fin 18. The sealing fin 18 is frusto-conically shaped,decreasing in size as it approaches the top panel 12. Preferably thesealing fin 18 in its undeformed condition is disposed at an angle of 25to 40 degrees from the longitudinal axis of the skirt 14. Such angle isdenoted by the letter A in FIGURE 1. The sealing fin 18 is joined to thetop panel 12 by two fillets 13 and 15, one on each side thereof.

The sealing fin 18 is relatively thin, on the order of .005 to .015" atthe free end and .010" to .030 at the joined end just below the fillets13 and 15. The top panel 12 and skirt 14 are substantially thicker thanthe sealing fin as is well known in the art. The closure may be formedof any desired material possessing the properties of flexibility andresilience in thin section (i.e., the sealing fin thickness).Polyethylene and polypropylene are cited as materials from which theclosure may be molded, however, these materials are cited for thepurpose of illustration and not limitation.

Referring now to FIGURES 2 and 3, there is provided a container 20 whichis especially designed for use in combination with the closure 10. Thecontainer 20 has a neck 22 with outwardly facing threads 24 adapted forholding engagement with the closure. threads 16. The neck 22 terminatesat its upper end in an annular rim 26 defining the periphery of an openmouth. The rim 26 includes a horizontal portion 27 and a downwardlytapering sealing portion 28 disposed outwardly therefrom. The horizontalportion 27 and the tapered sealing portion 28 meet at a breaking point29.

. It can be seen from viewing FIGURE 3 that the portion of the sealingfin 18 lower surface adjacent the top panel can never achieve contactwith the container sealing portion 28 because of the bulk of material inthe area where the sealing fin 18 joins the top panel 12. It has beendetermined that the point on the lower surface of the sealing finclosest to the top panel 12 capable of making contact with the sealingportion 28 is one which lies in vertical alignment with the point ofintersection between sealing fin centerline and the under surface of theclosure top panel 12. For purposes of orientation, vertical is definedas the longitudinal axis of the skirt 14 or any line parallel thereto.This point on the sealing fin 18 may be referred to as the ultimatecontact point 19.

The container neck 22 and rim 26 are sized relative to the closure 10such that the diameter of the circle defined by the breaking point 29 isno greater than the diameter of the circle defined by the sealing finultimate contact point 19 thus insuring that no part of the sealing finmakes firm contact with the horizontal portion 27. This is essential assuch contact may destroy the seal between the fin and the taperedsealing portion.

The included angle between vertical and the tapered sealing portion 28is approximately 60 to 75 degrees and is illustrated by the letter B inFIGURE 2.

Application of the closure 10 to the container 20 causes the lower freeend of the sealing fin 18 to initially engage the rim tapered sealingsurface 28 and be pushed upwardly and outwardly thereby (see FIGURE 2).Continued tightening of the closure on the container neck causes thesealing fin 18 to be further cammed upwardly and outwardly by thetapered sealing surface 28 until it reaches the position shown in FIGURE3 where a liquidtight seal is achieved. Such seal is especiallyeffective because of the fact that the sealing fin 18 is stretchedtightly over the container tapered sealing surfaces to achieve a firminterfacial engagement therewith. It can be noted from FIGURE 3 that thesealing contact between these surfaces is over a relatively wide area.Thus, by viewing the elements in section as in FIGURE 3, it may be seenthat contact is effected from the free end of the sealing fin to theultimate contact point 19.

The upward and outward urging of the sealing fin 18 is limited by thedegree of taper of the sealing surface 28. Such taper, within the limitspreviously noted, while causing sufficient stretching of the sealing fin18 to result in an effective seal, is sufficiently small to insure theattainment of an effective seal upon reapplication of the closure to thecontainer. In addition, by providing a closure-container combinationwhich effects sealing contact between two tapered members (the sealingfin 18 and the tapered sealing surface 28), the force resulting fromsuch sealing contact has a horizontal as well as a vertical component.The horizontal component in effect places the sealing fin 18 in hooptension against the sealing surface 28 thereby insuring that the freeend of the sealing fin 18, as well as.the other portions of the sealingfin up to the point of ultimate contact 19, is maintained in sealingcontact. Equally importantly, the sizing of the respective members tocause the point of ultimate contact 19 to hit the rim 26 on the taperedsealing surface 28 and not on the horizontal surface 27 insures that theentire length of the fin 18 from such point of ultimate contact 19 tothe free end engages such sealing surface.

It can be readily seen from the foregoing description that the presentinvention provides a novel and exceptionally effective container andlinerless closure combination which meets not only the requirement ofproviding a liquid tight seal upon initial sealing but also uponresealing.

It isobvious that many changes and modifications may be made in thisinvention without departing from its spirit and scope which is to belimited only by the following claims.

We claim:

1. In combination: a rigid container having an externally threaded neckportion terminating at its end in a annular rim defining the peripheryof an open mouth, said rim including a substantially fiat portion lyingin a plane normal to the longitudinal axis of said neck and a primarysealing portion disposed radially outwardly from said fiat portion, saidprimary sealing portion tapering downwardly from said fiat portion, theincluded angle between said sealing surface and said longitudinal axisbeing 60 to 70 degrees, said sealing surface following a substantiallystraight line element and intersecting said fiat portion in a breakingpoint, said breaking point defining a circle; and a closure affixed tosaid container comprising a top panel, an internally threaded skirtdepending from said top panel engaging said threaded neck, thelongitudinal axis of said skirt being aligned with the longitudinal axisof said neck portion, a resilient sealing fin depending downwardly andoutwardly from said top panel, the included angle between the sealingfin in an undeformed condition and said skirt logitudinal axis being 25to 40 degrees, the circle defined by the intersection of the sealing fincenterline and the under surface of said top panel being at least aslarge as the circle defined by said container rim breaking point, saidsealing fin maintained in sealing engagement with said container sealingsurface from the free end thereof to a point axially aligned with saidintersection between the sealing fin centerline and the top panel undersurface. I

2. In combination: a container having an externally threaded neckportion terminating at its end in an annular rim defining the peripheryof an open mouth, said rim including a substantially flat portion lyingin a plane normal to the longitudinal axis of said neck and a primarysealing portion disposed radially outwardly from said flat portion, saidprimary sealing portion tapering downwardly from said flat portion, saidsealing surface following a substantially straight line element andintersecting said fiat portion in a breaking point, said breaking pointdefining a circle; and a closure affixed to said container comprising atop panel, an internally threaded skirt depending from said top panelengaging said threaded neck, the longitudinal axis of said skirt beingaligned with the longitudinal axis of said neck portion, a resilientsealing fin depending downwardly and outwardly from said top panel, thecircle defined by the intersection of the sealing fin centerline and theunder surface of said top panel being at least as large as the circledefined by said container rim breaking point, said sealing finmaintained in sealing engagement with said container sealing surfacefrom the free end thereof to a point axially aligned with saidintersection between the sealing fin centerline and the top panel undersurface.

References Cited by the Examiner UNITED STATES PATENTS 2,039,345 5/1936Ravenscroft 21531 2,848,130 8/1958 Jesnig 215-31 2,886,198 5/1959 Herter215-31 3,053,406 9/1962 Wandell 215--43 X 3,055,526 9/1962 Plunkett215-43 X 3,072,277 1/1963 Hclfmann.

FOREIGN PATENTS 202,476 3/1959 Austria.

FRANKLIN T. GARRETT, Primary Examiner,

1. IN COMBINATION: A RIGID CONTAINER HAVING AN EXTERNALLY THREADED NECKPORTION TERMINATING AT ITS END IN A ANNULAR RIM DEFINING THE PERIPHERYOF AN OPEN MOUTH, SAID RIM INCLUDING A SUBSTANTIALLY FLAT PORTION LYINGIN A PLANE NORMAL TO THE LONGITUDINAL AXIS OF SAID NECK AND A PRIMARYSEALING PORTION DISPOSED RADIALLY OUTWARDLY FROM SAID FLAT PORTION, SAIDPRIMARY SEALING PORTION TAPERING DOWNWARDLY FROM SAID FLAT PORTION, THEINCLUDED ANGLE BETWEEN SAID SEALING SURFACE AND SAID LONGITUDINAL AXISBEING 60 TO 70 DEGREES, SAID SEALING SURFACE FOLLOWING A SUBSTANTIALLYSTRAIGHT LINE ELEMENT AND INTERSECTING SAID FLAT PORTION IN A BREAKINGPOINT, SAID BREAKING POINT DEFINING A CIRCLE; AND A CLOSURE AFFIXED TOSAID CONTAINER COMPRISING A TOP PANEL, AN INTERNALLY THREADED SKIRTDEPENDING FROM SAID TOP PANEL ENGAGING SAID THREADED NECK, THELONGITUDINAL AXIS OF SAID SKIRT BEING ALIGNED WITH THE LONGITUDINAL AXISOF SAID NECK PORTION, A RESILIENT SEALING FIN DEPENDING DOWNWARDLY ANDOUTWARDLY FROM SAID TOP PANEL, THE INCLUDED ANGLE BETWEEN THE SEALINGFIN IN AN UNDERFORMED CONDITION AND SAID SKIRT LONGITUDINAL AXIS BEING25 TO 40 DEGREES, THE CIRCLE DEFINED BY THE INTERSECTION OF